DELHI  AIR POLLUTION

1. Context

Delhi was once again covered in a haze of smog, witnessing very poor air quality, a phenomenon that has become a trend during the winter months.

 The share of vehicular exhaust contributing to Delhi's PM2.5 pollution is up to 30% while soil and road dust is up to 20%, biomass burning is 20%, industries are up to 15%, diesel generators up to 10%, power plants up to 5% and notably, the share of pollution from outside Delhi's urban airshed (like stubble burning in neighboring States) is up to 30%

2.PIL on High Pollution level

In March 1995, the Supreme Court, while hearing a plea by environmentalist and lawyer M.C. Mehta about Delhi’s polluting industries, noted that Delhi was the world’s fourth most polluted city in terms of concentration of suspended particulate matter (SPM) in the ambient atmosphere as per the World Health Organization’s 1989 report.

The Court took note of two polluting factors — vehicles and industries, and in 1996 ordered the closure and relocation of over 1,300 highly-polluting industries from Delhi’s residential areas beyond the National Capital Region (NCR) in a phased manner.

 In 1996, Mr. Mehta filed public interest litigation (PIL) alleging that vehicular emissions were leading to air pollution and that it posed a public health hazard. In the same year, a report about Delhi’s air pollution by the Centre for Science and Environment made the apex court issue a notice to the Delhi government to submit an action plan to curb pollution. Both matters were later merged

3.Perilous level of pollution in Delhi

UrbanEmissions.Info re-analyzed the pan-India PM2.5 concentration from 1998 to 2020 and found that Delhi was the most polluted of all States/UTs each year through all 23 years. Delhi's annual PM2.5 levels increased by 40% from 80 g/ m3 to 111 g/m3.

 Another study by the U.S. - based Health Effects Institute released this year, studying data between 2010 and 2019, also found Delhi to be the most polluted city in the world in terms of PM2.5 levels. In the winter of 2016, Delhi witnessed one of its worst incidents of pollution-induced smog, with PM2.5 and PM10 levels reaching a whopping 999 ug/m3 in parts of Delhi on November 1.

4.Measures are taken to Curb Pollution

4.1.Environmental Pollution Control Authority of Delhi NCR (EPCA)

The Supreme Court, recognizing the need for technical assistance and advice in decision-making and implementation of its orders, asked the Ministry of Environment and Forests (now the Ministry of Environment, Forests, and Climate Change — MoEFCC) to establish an authority for Delhi, leading to the creation of the Environmental Pollution Control Authority of Delhi NCR (EPCA) in 1998

• The EPCA submitted its report containing a two-year action plan in June of that year and the Supreme Court subsequently ordered the Delhi Trasport Corporation (DTC) bus fleet, taxis, and autos to switch to Compressed Natural Gas (CNG), and the phasing out of all pre-1990 autos.
• Other measures between the late 1990s and early 2000s included the complete removal of leaded petrol, removal of 15 and 17-year-old commercial vehicles, and a cap of 55,000 on the number of two-stroke engine auto rickshaws (which reports at the time said were contributing to 80% of pollution in the city).
• Coal-based power plants within Delhi were also converted to gas-based ones.

The Centre decided to establish a network of monitoring stations under the National Air Quality Programme (NAMP) to measure key pollutants. Under the National Ambient Air Quality Standards (NAAQS) specified by the Central Pollution Control Board (CPCB), pollutants like PM10 (particulate matter with a diameter exceeding 10 microns), sulphur dioxide, and nitrogen oxides were measured.

4.3.Graded Response Action Plan (GRAP)

 The Supreme Court in November 2016 told Delhi and NCR authorities to form a plan to deal with the air pollution, and the MoEFCC in early 2017 came out with the Graded Response Action Plan (GRAP), which involved coordination between multiple agencies in Delhi to activate pollution control measures corresponding to the increasing Air Quality Index (AQI) levels.

 5.Revised standards of Air quality 

The NAAQS was revised in 2009 to include 12 categories of pollutants including PM2.5 (particulate matter with a diameter under 2.5 microns) — noxious pollutants which can penetrate deep into the lungs and even enter the bloodstream, resulting in cardiovascular and respiratory impacts.

 Particulate Matter (PM) is primarily generated by fuel combustion from different sectors, including transport, energy, households, industry, and agriculture. According to the revised NAAQS, the acceptable annual limit for PM2.5 is 40 micrograms per cubic metre (ug/m3) and 60 ug/m3 for PM10. The renewed WHO standards meanwhile, prescribe an accepted annual average of 5 ug/m3 for PM2.5 and 15 ug/m3 for PM10. While PM2.5 as a pollutant was only included in 2009

6.Causes Behind High Pollution level in Delhi

6.1.Rapid growth in Delhi’s population: Population density grew from 9,340 persons per sq km in 2001 to 11,320 persons per sq km in 2011

 6.2.Industrialization : The Najafgarh drain basin, which houses multiple industrial areas, is the most polluted cluster in India with its air and water being in the ‘critical’ category

 6.3.Urbanization: Increase in motorized private vehicle fleets led to the high concentration of air pollutants such as particulate matter, nitrogen oxides, sulphur dioxide, carbon monoxide, and ozone. From around 4.2 million motor vehicles registered in 2004 in Delhi alone, the registered vehicles increased to around 10.9 million in March 2018

7.Loopholes And Solutions

Multiple researchers have alleged that the policy approach and measures taken by the Central and State authorities for specific polluting sectors over the years have been fragmented and often reactive

Due to the Supreme Court’s 55,000 cap on two-stroke auto rickshaws, the sector could not grow, leading to black marketing of permits. Studies note that between 1997 and 2011, Delhi’s population grew by 45% and registered cars and two-wheelers grew by 250%, meaning the lower availability of autos could have likely contributed to increased private vehicle ownership. Besides, Delhi still does not have the required public bus fleet vis-a-vis demand

Although vehicular emissions contribute 25% to Delhi’s PM2.5 levels, passenger vehicles contribute just 8%, of which cars constitute 5%. This means that if all passenger vehicles within Delhi stopped operating, PM2.5 levels would reduce by an average of 8%, but the remaining 17%, contributed by heavy freight vehicles, would remain as it is not covered under the odd-even rule. Experts also point out that a coordinated response factoring in Delhi’s waste management has to be taken to reduce air pollution.

While the daily waste generation rate in Delhi is over 10,000 tons, the capacity of its already overflowing landfills to collect and manage garbage is under 6,000 tons. This leads to the practice of burning waste around residential areas

Burning of farm residue or stubble in Delhi’s neighbouring States, Haryana, Punjab, Uttar Pradesh, and Rajasthan, researchers have emphasized the need for airshed management, along with improved machinery subsidies from the government and alternatives to crop burning. An airshed is a common geographic area where pollutants get trapped